It mainly includes the recurrent expenditure of national defense and armed police forces, national defense scientific research expenditure, military investment expenditure, militia business expenditure, strategic material reserve expenditure and war expenditure. The defense expenditure mainly comes from the national financial revenue, which is a part of the national income created by the social material production department. In addition, there are military production and management, war reparations, foreign military assistance and other income. It also constitutes the source of national defense funds. After the national financial budget and the allocation of funds to various departments of the national defense system, the defense expenditure has finally formed two large pieces: one is the funds for military investment and national defense engineering investment, and the other is the funds for military special goods consumption and personnel living consumption. The main economic activities in the national defense system use the funds at their disposal to purchase means of production, military special goods or consumer goods, and complete the movement of the value form and physical form of national defense funds. The purpose of the national defense fund is to safeguard national security and maintain world peace.